D$1$ Surface Integrals: Problem $2$

$(1$ point$)($a$)$ Find a vector parametric equation for the ellipse that lies on the plane $x-2y+z=-7$ and inside the cylinder $x^2+y^2=49.$

vec$(r)(u,v)=$ for

$0u7$ and $0v2.$

$($b$)$ vec$(dA)=$vec$(r{)}_u$vec$(r{)}_v=$